Fernandez's strikeout total matched Josh Beckett's team record for an opener. Fernandez threw 73 strikes and only 21 balls to 23 batters.
The crowd included Fernandez's grandmother Olga, who lives in Cuba. She saw him pitch for the first time since he left that country at age 15.
Her grandson improved to 10-0 in 16 career starts at Marlins Park with an ERA of 1.21.
"She told me, 'Good pitching. You've got to throw a lot more strikes, though,'" Fernandez said.
He threw plenty, given his improved run support. The Marlins, who finished last in the majors in most offensive categories last year, totaled 14 hits while scoring in double figures, something they did only four times in 2013.
Marcell Ozuna homered, doubled, singled and scored twice. Giancarlo Stanton had an RBI infield single and a run-scoring double. Adeiny Hechavarria singled three times and drove in a run.
NOTES: Marlins INF Rafael Furcal, who began the season on the DL with a strained left hamstring, said he expects to play five or six games on a rehabilitation assignment. He hopes to be activated around April 14. ... Weiss had two hits and two RBIs when he started at SS in the Marlins' first game 21 years ago. ... The Marlins' bid for back to back no-hitters ended with the second batter, when Cuddyer singled. Henderson Alvarez pitched a no-hitter for Miami on the final day of last season. ... Miami's Nathan Eovaldi is scheduled to start against Brett Anderson on Tuesday.